/Engine/Source/Runtime/Engine/Classes/GameFramework/InputDeviceSubsystem.h
Gets the most recently used hardware input device for the given platform user
[FHardwareDeviceIdentifier](API\Runtime\Engine\GameFramework\FHardwareDeviceIdentifier) GetMostRecentlyUsedHardwareDevice ( const [FPlatformUserId](API\Runtime\Core\Misc\FPlatformUserId) InUserId ) const